The present invention relates to a rotating drum separator useful for separating fibers from fines in an air flow.
Rotating drum separators have been widely used in the past in applications such as air filtration and tobacco separation. U.S. Pat. Nos. 2,009,140, 3,472,002, 3,667,195, and 4,222,754 provide several examples of air filters based on the rotating drum principle. In each case, substantially the entire periphery of the drum is exposed to the air flow to be filtered, and air velocity through the screening medium of the drum is thereby minimized. U.S. Pat. Nos. 2,783,888 and 3,727,755 illustrate pneumatic separators used to separate tobacco leaves from stems and the like.
Air filtration applications and tobacco separation applications differ in important respects from the problems solved with the present invention. In particular, the preferred embodiments described below of the drum separator of this invention operate to segregate fines from fibers in an air flow in a rapid and efficient manner.